US 12,391,866 B2
Surfactant mixtures for enhanced oil recovery
Limin Xu, Beijing (CN); Ming Han, Dhahran (SA); and Tianping Huang, Beijing (CN)
Assigned to Saudi Arabian Oil Company, Dhahran (SA)
Filed by Saudi Arabian Oil Company, Dhahran (SA)
Filed on Jul. 11, 2023, as Appl. No. 18/350,469.
Prior Publication US 2025/0019586 A1, Jan. 16, 2025
Int. Cl. C09K 8/584 (2006.01)
CPC C09K 8/584 (2013.01) 21 Claims
OG exemplary drawing
 
1. An enhanced oil recovery (EOR) fluid, comprising:
a base fluid comprising a high salinity brine wherein the brine has a salinity in a range of about 14,000 ppm to about 87,000 ppm;
a first surfactant comprising an anionic-nonionic surfactant selected from the group consisting of sodium alkylphenol ethoxylate carboxylate (APEC), sodium alkyl ethoxylate carboxylate (AEC), sodium alkylphenol ethoxylate sulfate (APES), and sodium alkyl ethoxylate sulfate (AES); and
a second surfactant comprising a cationic surfactant comprising an alkyl pyridine salt;
wherein the EOR fluid has a temperature between about 80° C. and about 90° C.; and
wherein the base fluid comprises a 0.2 weight percent mixture of the first surfactant and the second surfactant in the base fluid.